According to experts, the eCommerce market share in 2019 was $3.535 trillion. It's impressive. Though, it's impossible to achieve and support such sales rates without less visible but not less impressive pay system development efforts.
We have been working with pay systems since their first appearance on the Internet. We have integrated payment systems with user systems, built our systems, modified payment gateway modules, etc.
What is more, we have gained considerable experience in quality assurance testing of such implementations.